Several samples of seawater (43,000 mg/l) were circulated at a high intensity (7,000 gauss) through a permanent magnetic tube for several hours at fixed temperature, flow rates, and nitrogen concentration. The pH and conductivity of all samples were increased during the circulation time. Using Reverse Osmosis (RO), both treated and untreated solutions were desalinated in a seawater RO unit at several pressures. It was found that the permeate salt concentrations of the treated solutions were usually lower than that for untreated ones. The effect of the magnetic field on pH and conductivity were gradually eliminated when the treated solutions were circulated in absence of the magnetic device.